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Dub, I know how that feels, when you have something in your mind's eye and then it turns out to be something completely different. That being said, it looks nice and will look even better once the case is built and covered.

After several attempts at changing resistors on the bias supply and not being able to get the tubes biased in a proper range, I decided to ad a 10K bias trim pot. I followed the layout of the AA864 Bassman which is the next version after this one. I just finished wiring it and since it's getting late hopefully I can get the tubes biased properly tomorrow. I used a long shaft pot and cut the extension short and slotted it so I can adjust it from bottom or top side of the chassis. I have one of those bias-rite adaptors so I'll be able set the bias from top or bottom of the chassis.



BTW, I ordered the blonde tolex and wheat gold grill cloth today from Mojo. Hopefully it will accent the gold face plate in a pleasing manner. If not I guess I can send it to ludobag in France.

Next is the part I hate. That's building the cabinets for the head and speakers.

Skookum wiring! Ain't that the case, with every hobby project comes a part we hate... I'm slowly coming around to doing finishes after I broke down and bought myself a palm-sander...sure beats the old manual rub-rub-rub! I built some Peavey SP-5 clone cabinets, and used birch plywood, nice to work with, and makes a good tight-sounding cabinet.

Dub, what were the outputs biased at with the original fixed resistor? And what was the bias voltage?

Where are you planning on setting the bias?

Mr. Bill wrote:Dub, what were the outputs biased at with the original fixed resistor? And what was the bias voltage?

Where are you planning on setting the bias?

Before I changed it to a bias pot I was reading the multimeter wrong. I thought it was auto adjusting and I had it set on DC volts and couldn't get it into the milliamp range. After several tries at swapping out resistors and testing, I decided to change it over to bias trim pot, however I was still not getting a milliamp reading. Finally after staring at the meter trying to figure out what was wrong I suddenly realized it had to be manually set on MA. Yep, dumb me!

At any rate, the plate voltage is 470v and I have the bias set at 35.2 MA. With the bias probe tool that goes between the tube and the socket it sure makes it easy to set the bias now that I learned how to set the meter to the right function. Lesson learned.......the hard way.

I used the Weber bias calculator as a guide for a ball park setting. http://www.webervst.com/tubes1/calcbias.htm

Skookum wiring! Yeah, I like that.

Wood working is not my cup of tea, but it has to be done. First I had to research the internet for finger jointing, then I had to make a jig. I got the jig made and then had to learn how to use it. This was at the the expense of trial and error. Even though I got it working OK on scrap material, the alignment was off on the actual cabinet. Fortunately with a little creative saw work I salvaged the project, albeit with some wide spacing in a few spots.

Danny, that looks really nice and clean!

--Jim

Looks really good Danny! That's a pretty smart jig, even if it didn't work exactly right, it beats having to buy a specialized tool if you can avoid it.

Gee, is there anything that you can't do?

Danny, I'm not a wood worker but common sense tells me you got the grain facing in the right direction for those finger joints, so they can't snap off easily.
And "a little creative saw work" is proof of a handcrafted piece of art
Looking good!